Blank shingling mechanism for envelope forming machine



Nov. 18, 1969 F. T. KNA-PP 3,479,025

BLANK SHINGLING MECHANISM FOR ENVELOPE FORMING MACHINE Filed Oct. 9, 1967 4 Sheets-Sheet 1 INVENTOR. FRANK THOMAS KNAPP ATTORNEYS Nov. 18, 1969 F. 'r. KN-APP 3,479,025

BLANK SHINGLING MECHANISM FOR ENVELOPE FORMING MACHINE Filed Oct. 9, 1967 4 Sheets-Sheet 2 F. T. KNAPP Nov. 18, 1969 BLANK SHINGLING MECHANISM FOR ENVELOPE FORMING MACHINE 4 Sheets-Sheet 5 FiIed Oct. 9, 1967 Nov. 18, 1969 F. T. KNAPP 3,479,025

BLANK SHINGLING MECHANISM FOR ENVELOPE FORMING MACHINE Filed Oct. 9, 1967 4 4 Sheets-$heet 4 United States Patent 3,479,025 BLANK SHINGLING MECHANISM FOR ENVELOPE FORMING MACHINE Frank T. Knapp, Chicopee Falls, Mass., assignor to United States Envelope Company, Springfield, Mass., a corporation of Maine Filed Oct. 9, 1967, Ser. No. 673,770 Int. Cl. B65h 29/60 US. Cl. 271-2 9 Claims ABSTRACT OF THE DISCLOSURE In an envelope forming machine wherein folded blanks are advancing at high speed a pair of belt conveyors engage the marginal side edges of the underside of each successive blank to decelerate it, and a rotating finger lifts the trailing top flaps of the most recently decelerated blanks so that the next succeeding blank is fed therebeneath. A pair of deadplates are provided adjacent the upstream ends of these belt conveyors, and a pair of snubber wheels are adjustably mounted above each belt conveyor to hold the decelerated blanks against the conveyors so that the top flaps thereof can be so lifted by the rotating finger.

SUMMARY OF INVENTION This invention relates to envelope forming machines, and deals more particularly with a mechanism for shingling the envelope blanks after they have been folded so that the seal flaps, or top flaps as they are sometimes called, can be collectively glued by a conventional glue applying roller rotating continuously on a fixed axis.

A general object of the present invention is to provide a shingling mechanism wherein prefolded envelope blanks are simultaneously decelerated on suitable belt conveyor means, and have their trailing top flaps lifted upwardly in order to provide an opening for the next succeeding envelope blank.

Another object of the present invention is to provide an envelope blank shingling mechanism which is adjustable to accommodate prefolded envelopes of various size.

Still another object of the present invention is to provide an envelope blank shingling mechanism wherein a movable finger successively lifts each envelope seal flap, or top flap, in order to provide an opening for the next succeeding blank to the decelerated.

The drawings show a preferred embodiment of the invention and such embodiment will be described, but it will be understood that various changes may be made from the construction disclosed, and that the drawings and description are not to be construed as defining or limiting the scope of the invention, the claims forming a part of this specification being relied upon for that purpose.

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a side elevational view of a shingling mechanism incorporating the present invention, wherein the envelope blanks are fed from right to left.

FIG. 2 is a vertical sectional view taken along the line 22 of FIG. 1.

FIG. 3 is a vertical sectional view taken along the line 3-3 of FIG. 1.

FIG. 4 is an elevational somewhat schematic view showing the rotating finger for lifting the trailingtop flap of the envelope blanks as they are decelerated on the belt conveyor.

FIG. 5 is similar to FIG. 4 but shows the finger at a slightly later instant of time.

FIG. 6 is a view similar to FIGS. 4 and 5 but showing the finger at still later instant of time.

3,479,025 Patented Nov. 18, 1969 ice DETAILED DESCRIPTION Turning now to the drawings in greater detail, FIG. 1 shows a portion of an envelope forming machine wherein envelope blanks are fed from right to left through a shingling mechanism of the present invention. The envelope blanks entering the right hand portion of the mechanism will preferably have been prefolded, and the bottom flaps! adhesively attached to the infolded side flaps in a well known manner. Whereas the conventional practice involves shingling blanks in which the bottom flap is not prefolded, it will be apparent that in this disclosure the bottom flap is prefolded so that bottom fold or score line comprises the leading portion of the blank entering the right-hand end of the mechanism shown in FIG. 1. Thus, the top flap, which is in an open condition, will comprise the trailing end portion of the envelope blank entering the shingling mechanism. The shingling mechanism shown is adapted to decelerate these prefolded envelope blanks so as to shingle them one under the other, whereby a continuously rotating glue applying roller at a downstream station (not shown) can apply a continuous coating of moistenable adhesive to the exposed upper surface of these top flaps. Although the actual gluing station is not shown in the drawings, such apparatus is well known in the art, being shown and described for example in US. Patent No. 2,132,227 issued to Winkler et al.

The portion of the envelope forming machine shown in the drawings comprises a fixed frame 10 and a fixed vertical support 12 connected to a common base 14. Looking in the downstream direction, as in FIG. 2, the abovedescribed members comprise the left-hand portion of the fixed frame of the machine, and it will be apparent that a similar structure is provided at the right-hand side of the machine as shown at 10a, 12a and 14a.

An upstream portion of the machine (not shown) is provided for advancing envelope blanks flatwise in longitudinally spaced relation with the top flaps trailing, through the shingling mechanism of the present invention. These blanks may be advanced between rotating feed rollers, and it is a feature of the present invention that the belt 16 is driven from the same source as such feed rollers. A pulley 18 on shaft 20 causes the gears 22 and 24 to be driven at a predetermined peripheral speed dictated by the speed of the belt 16. The shaft 20 carries a pair of envelope advancing rolls 26, 26 the peripherys of which move at the same speed as the periphery of a back-up roll 28 driven by the gear 24. The peripheral speed of the rolls 26, 26 and back-up roll 28 match as a result of the relative diameters of the gears 22 and 24. As best shown in FIGS. 4, 5, 6 and 7, the blank advancing rolls 26, 26 are preferably semi-circular in shape so as to advance an envelope blank between themselves and the back-up roll 28 only during approximately one half of their angular travel. Feed rolls located upstream of the rolls 26, 26 and back-up roll 28 are provided for continuously advancing envelope blanks toward the shingling mechanism.

As best shown in FIG. 3, a laterally extending cross member 30 is fixed at either end in the fixed frame of the machine as shown at 32 and 32a. A pair of laterally adjustable vertically extending end plates 34 and 34a are slidably received on the fixed guide member 30 and on a similar guide member located downstream thereof (not shown). Means is provided for moving the end plates 34 and 34a toward and away from one another in synchronism with each other in order to accommodate envelopes of various lateral dimension. The aforesaid means comprises no part of the present invention, being mentioned herein solely for purposes of clarity. Each of the end plates 34 and 34a carries a continuously moving belt conveyor 36 and 36a, which belt conveyors engage the underside of the advancing envelope blank 38 and more particularly the marginal side edge portions thereof.

As best shown in FIG. 1, each endless belt 36 and 36a, is continuously driven in the direction of the arrow 37 at a slower speed than the peripheral speeds of the envelope blank advancing rolls 26, 26 by suitable means (not shown). More particularly, the belt 36 passes around rolls 40 and 42, as well as around other suitable rolls (not shown) so that a straight upper run of said belt engages the underside of the advancing blanks to decelerate said blanks longitudinally at an upstream portion of said belt conveyor. A back-up support structure 44 is provided for the upper run of the belt 36 so as to assure engagement with the underside of the decelerated envelope blanks. A gravity biased back-up roll 46 is associated with each belt conveyor, 36 and 36a, for maintaining the envelope blanks in contact with the sub-adjacent belt 36. The roll 46 is mounted on the free end of a lever arm 48 pivotally supported in the plate 34 as shown.

In accordance with the present invention, deadplate means is provided adjacent the upstream end of each of the belt conveyors 36 and 36a, for guiding each of the envelope blanks advanced between the rolls 26, 26 and the back-up roll 28 so that the leading edge of the blank engages the decelerating belt 36, and so that the trailing top flap of such blank is engaged by an upwardly moving finger 50. The finger 50 is rotatably mounted so as to lift the trailing top flap of the blank being decelerated in order to provide an opening for the next succeeding envelope blank in the shingling mechanism of the present invention. The deadplate means associated with each of the belt conveyors 36 comprises a teflon coated glass cloth tape 52 arranged above the upper surface of the upstream portion of the belt conveyor 36 and extending upstream from this position around the upper surface of the backup roll 28, and thence curving downwardly as shown in FIG. 1 with the lower end portion of the tape being spring-biased as shown at 54. Each of the deadplate means is of approximately the same width as the belt conveyor 36 so as to engage only the marginal side edge portions of the advancing blank. While any relatively low friction material might be used for the deadplates 52, 52 the tefion coated glass cloth has been found to be especially satisfactory because of its tendency to reduce any static friction built up on the envelope blanks.

In further accordance with the present invention an envelope blank snubber wheel is rotatably mounted adjacent the upstream portion of each of the belt conveyors 36 and 36a, and the snubber wheels are biased downwardly for urging the blanks into contact with the belt conveyor. Preferably, the snubber wheels are located in longitudinally spaced relation to the path of movement of the fingers so that the envelope blank being decelerated has its leading edge snubbed thereby at substantially the same time that its trailing top flap is being lifted by the finger 50.

It is a feature of the present invention that the snubber wheels 60 and 60a are adjustably mounted longitudinally, in the direction of travel of the blanks, so that envelope blanks of various height can be handled by a shingling mechanism of the present invention. The snubber wheel 60 is rotatably supported on a pin 62 carried at the lower end of a lever arm 64 pivotally secured at its upper end in a slide block 66. The slide block 66 is slidably received in a suitable way 68 defined in the end plate 34 as best shown in FIG. 1' The longitudinally extending way 68 comprises a generally rectangularly shaped opening parallel to the upper run' of the conveyor belt 36Q'Me'zins is provided for moving the slide block 66, and an associated slide block 66a, in unison with one another longitudinally of the way 68 so that the snubber wheels 60 and 60a can act upon the envelope blank being decelerated at the same time that the trailing top flap of said blank is being lifted by the finger 50. Coiled torsion springs, 68 and 68a, are provided between the slide blocks, 66 and 66a, and their associated lever arms, 64 and 64a, so as to urge each of the snubber wheels, 60 and 60a, into contact with the most recently decelerated envelope blanks.

Turning now to a more detailed description of the means for adjustably positioning the snubber wheels, 60 and 60a, with respect to the path of movement of the finger 50, FIG. 3 shows each slide block, 66 and 66a, as having a belt follower, 70 and 70a respectively, attached to the outer side thereof for attachment to associated adjustment belts, 72 and 72a. As best shown in FIG. 1, the belt 72 includes a lower run generally parallel the longitudinally extending way 68, and is entrained over a series of pulleys 74, 76, 78 and 80. The opposite, or righthand adjustment belt 72a, is similarly supported and a cross shaft 82 connects the pulleys 76 and 76a so as to permit simultaneous movement of both slide blocks, 66 and 66a, in response to rotation of a hand knob 84 provided at the front, or left-hand side, of the machine frame. A locking device is provided, as indicated at 86, to permit locking of the shaft 82 after an adjustment has been made to the snubber wheels.

It is an important feature of the present invention that the finger 50 is rotatably supported above the longitudinal part of movement of the envelope blanks on the cross shaft 20 and that said finger is arcuate in shape and curved radially outwardly and forwardly in the direction of rotation of said shaft 20. Thus, the end portion of the finger 50 is adapted to move downwardly from the position shown in FIG. 4 to that depicted in FIG. 5 so as to engage the trailing top flap of the envelope blank and to raise said blank after its leading edge has been decelerated by the conveyor 36 to the position shown in FIG. 6. Further rotation of the finger 50 to the position depicted in FIG. 7 causes the most recently decelerated envelope blanks to be lifted as shown. The finger 50 is mounted on a semi-circularly shaped member and it will be apparent that the periphery of the member 90 serves to hold the envelope blanks in a lifted condition until the next succeeding envelope blank is shingled therebeneath. As shown in FIGS. 4 and 5, and depending upon the size of the envelope blanks being handled, the semicircular blank advancing rolls 26, 26 also serve to maintain the most recently decelerated blanks in a lifted condition until the rotating finger 50 has reached substantially the position shown in FIG. 6. In this particular angular orientation of the member 90, and of the semicircular feed rolls 26, 26 the envelope blanks are allowed to snap back slightly onto the upwardly moving finger 50.

It is a further feature of the present invention that the downstream end of the deadplate 52 is mounted in close proximity to the snubber wheel 60 so that the envelope blank to be decelerated is held oif the slowly moving belt 36 until the leading edge of said blank engages the snubber wheel 60 or the underside of the previously decelerated blanks. In order to assure that the downstream end of the deadplate 52 is always so arranged in spite of adjustments made to the longitudinal position of the snubber wheel 60, angle brackets 92 and 92a are provided on each of the slide blocks 66 and 66a for so supporting the downstream end of the deadplates or tapes 52 and 52a. These angle brackets 92 or 92a are best shown in FIG. 3.

I claim:

1. In an envelope forming machine of the type having means for advancing prefolded envelope blanks flatwise in longitudinally spaced relation with their top flaps trailing, the improvement comprising continuously moving conveyor means for engaging the underside of said advancing blanks to decelerate said blanks longitudinally, a finge'r movably mounted adjacent an upstream end of said conveyor for lifting the trailing top flaps of said decelerated blanks so that said blanks are successively shingled one beneath the other on said conveyor means, deadplate means adjacent the upstream end of said conveyor means, said blanks being advanced onto said deadplate means by said aforementioned blank advancing means, and said finger being movable upwardly through said deadplate means to lift the trailing top flap of the blank as the leading edge of said blank is being decelerated by said conveyor means.

2. The combination set forth in claim 1 further characterized by at least one envelope blank snubber wheel rotatably mounted above said conveyor means and means biasing said wheel downwardly for urging said decelerated blanks into contact with said conveyor means.

3. The combination set forth in claim 2 further characterized in that said snubber wheel is located in longitudinally spaced relation to the path of movement of said finger so that the envelope blank being decelerated has its leading edge snubbed at substantially the same time that its trailing top flap is being lifted by said finger.

4. The combination set forth in claim 3 further characterized by means for adjustably mounting said snubber wheel longitudinally in the direction of travel of said blanks so that envelope blanks of various size can be handled by the machine.

5. The combination set forth in claim 4 further characterized in that two laterally spaced snubber wheels are provided, said means for adjustably mounting said snubber wheels comprising two laterally spaced longitudinally extending fixed ways, a pair of endless belts having respective portions parallel to said ways, a block slidably mounted on each way and carrying one of said snubber wheels, and manually operable means for simultaneously moving said endless belts to vary the position of said wheels longitudinally as aforesaid.

6. In an envelope forming machine of the type having means for advancing prefolded envelope blanks flatwise in longitudinally spaced relation with their top flaps trailing, the improvement comprising continuously moving conveyor means for engaging the underside of said advancing blanks to de'celerate said blanks longitudinally, a finger movably mounted adjacent an upstream end of said conveyor for lifting the trailing top flaps of said decelerated blanks so that said blanks are successively shingled one beneath the other on said conveyor means, a cross shaft for rotatably supporting said finger above the longitudinal path of movement of said envelope blanks, said finger being arcuate in shape and curved radially outwardly and forwardly in the direction of rotation of said cross shaft, and means carried by said cross shaft for holding the trailing top flaps of the most recently decelerated envelope blanks in a lifted condition at least when the next succeeding blank is being shingled therebeneath.

7. The combination set forth in claim 6 further characterized in that said conveyor means comprises a pair of laterally spaced belt conveyors for engaging the marginal side edges of said blanks, a pair of deadplates adjacent the upstream ends of said belt conveyors, said blanks being advanced ontosaid deadplates by said aforementioned blank advancing means, and said finger being moveable upwardly between said deadplates to lift the trailing top flap of each blank as the leading edge of said blank is being decelerated by said belt conveyors.

8. The combination set forth in claim 7 further characterized by two laterally spaced snubber wheels rotatably mounted above said belt conveyors respectively, said snubber wheels being located in longitudinally spaced relation to the path of movement of said finger so that the envelope blank being decelerated has its leading edge snubbed at substantially the same time that its trailing top flap is being lifted by said finger, and means biasing said wheels downwardly for urging said decelerated blanks into contact with said belt conveyor.

9. The combination'set forth in claim 8 further characterized by means for adjustably mounting said snubber wheels longitudinally in the direction of travel of said blanks so that envelope blanks of various size can be handled by the machine.

References Cited UNITED STATES PATENTS 3,096,977 7/1963 Winkler 93-62 FOREIGN PATENTS 739,010 10/1932 France.

RICHARD E. AEGERTER, Primary Examiner US. Cl. X.R. 9362 

